Trigonometric Equations - Double Angle Identity Types

Examples, solutions, videos, activities and worksheets that are suitable for A Level Maths.
How to solve trig. equations that require the use of the double angle identities?

Trig. Equations: Double Angle Identity Types: (Example 4)
In this series of tutorials you are shown several examples on how to solve trig. equations that require the use of the double angle identities.
Example:
Solve sin 2x = sin x, for 0° ≤ x ≤ 360°

Trig. Equations: Double Angle Identity Types: (Example 5)
In this series of tutorials you are shown several examples on how to solve trig. equations that require the use of the double angle identities.
Example:
Solve sin(x/2) + cos x = 2, for 0° ≤ x ≤ 360°

Trig. Equations: Double Angle Identity Types: (Example 6)
Example:
Solve 3 tan x = tan 2x, for 0° ≤ x ≤ 2π

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